In wireless network communications, the network environment is an important factor that determines the communication quality. In order to ensure the communication quality in different network environments, various base stations (BSs) have been developed. Specifically, the communication quality of wireless networks is often restricted by environmental factors (e.g., being blocked by buildings or due to indoor network environments); therefore, in addition to the costly macrocells, low-cost base stations with a small output power and a low processing capability have also been developed to extend application environments of wireless networks. Through wide deployment of such low-cost base stations, the influence of environmental factors on communication quality of wireless networks can be effectively avoided. Among these low-cost base stations, femtocells have become a focus of development at present.
Further speaking, a lot of femtocells may be deployed in a wireless network to reduce the influence of environmental factors on communication quality of the wireless network, and in this case, macrocells connected to the femtocells are used for allocation of network resource blocks. However, if a macrocell fails to allocate network resource blocks to femtocells in an efficient way when a lot of femtocells exist in a network environment simultaneously, then it is likely that signals transmitted by the femtocells will collide with each other to cause interferences. In view of this, many approaches have been proposed to reduce interferences of femtocells.
In the prior art, one of the approaches to avoid interferences between femtocells is to exchange respective network resource usage statuses between femtocells. In detail, femtocells in a network can learn each other's resource block usage statuses through exchanging information with each other. In this way, use of resource blocks can be coordinated among the femtocells to reduce interferences caused by signal collisions. However, when this approach of exchanging information between femtocells is used to reduce the interferences, each femtocell must receive and process information transmitted from other femtocells; and consequently, the femtocells having only a limited computational capability have to consume a high percentage of computational resources in coordinating the allocation of resource blocks.
Accordingly, an approach of randomly allocating resource blocks has also been proposed to avoid consumption of a high percentage of femtocells' computational resources in coordinating the allocation of resource blocks. In detail, in this approach, resource blocks are randomly allocated by a macrocell to individual femtocells; and because this makes it unnecessary for the femtocells to exchange information therebetween, the computational burden on the femtocells is greatly eased. However, although allocating resource blocks randomly can ease the computational burden on the femtocells, the results of random allocation may cause instability of signal collision rates between the femtocells.
Therefore, an urgent need exists in the art to provide a solution that can reduce interferences caused by signal collisions between femtocells in a network environment having a lot of femtocells and can keep the computational burden on the femtocells at a reasonable level so that network resources can be used more efficiently.